Abstract

Drug eluting beads (DEB) are employed in the treatment of solid hypervascularised malignant tumours by a method called trans-arterial chemoembolisation (TACE). When the microcirculation to a tumour is blocked, oxygen levels decrease to critically low levels causing the tumour to become hypoxic. Hypoxic tumours are known to be chemoresistant and send out growth factor signals leading to angiogenesis and metastasis of tumour cells to other parts of the body. Commercially available DEB are unable to respond to the conditions of hypoxia and will continue to release drug at a constant rate via ionic exchange through the hydrogel. It is therefore recognised that an avenue for improvement would be the development of novel bioresponsive DEB that are able to react to the conditions of hypoxia to overcome chemoresistance associated with the tumour cells.